We will study the biochemical principles which permit the selective expression of specific genes leaving others transcriptionally inactive. More specifically, we wish to identify chromosomal nonhistone proteins responsible for the regulation of specific genes. We also plan to investigate the relationship between the structure and function of chromatin and the various chromosomal components. Because we believe that cancerous growth is the manifestation of erroneous genetic controls, we plan to study the expression of selected genes which are activated or inactivated during malignant transformation. The heterogeneity, tissue specificity, biosynthesis, interactions and gene regulatory properties of chromosomal nonhistine proteins will be investigated. The immunological specificity of chromosomal nonhistine protein-DNA complexes will be employed in the characterization of these antigens.